催化学报 ›› 2016, Vol. 37 ›› Issue (6): 963-970.DOI: 10.1016/S1872-2067(15)61092-0

• 论文 • 上一篇    下一篇

负载型铜钴氧化物协同催化H2O2/HCO3-降解苯酚

李一冰a,b, Ali Jawadb, Aimal Khanb, 卢小艳b, 陈朱琦b, 刘卫东a, 尹国川b   

  1. a 浙江师范大学化学与生命科学学院, 浙江金华 321004;
    b 华中科技大学化学与化工学院, 湖北武汉 430074
  • 收稿日期:2016-03-26 修回日期:2016-03-29 出版日期:2016-05-30 发布日期:2016-05-30
  • 通讯作者: Guochuan Yin
  • 基金资助:

    国家自然科学基金(20921092, 21227801); 湖北省楚天学者基金.

Synergistic degradation of phenols by bimetallic CuO-Co3O4@γ-Al2O3 catalyst in H2O2/HCO3- system

Yibing Lia,b, Ali Jawadb, Aimal Khanb, Xiaoyan Lub, Zhuqi Chenb, Weidong Liua, Guochuan Yinb   

  1. a College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, Zhejiang, China;
    b Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
  • Received:2016-03-26 Revised:2016-03-29 Online:2016-05-30 Published:2016-05-30
  • Contact: Guochuan Yin
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (21273086) and Chutian Scholar Foundation from Hubei Province, China.

摘要:

近年来, 环境污染特别是水的严重污染使其治理成为一个极具挑战性的课题. 各种污染物复杂的化学成分和催化剂在处理过程中的浸出、寿命及成本等问题是导致众多氧化催化剂难以实际应用的主要原因. 相对而言, H2O2 是一种活性氧含量高、清洁并可在温和条件下使用的氧化剂, 在各种高级氧化技术中受到广泛关注. 而碳酸氢盐是一种弱碱性物质, 在自然界及水体系中广泛存在, 且无明显毒害. 它可活化 H2O2, 加快其氧化各种有机物, 并在废水处理领域开始受到关注. 该体系的明显优势在于处理体系始终处于微碱性环境, 可以有效避免金属氧化物催化剂在处理过程中由于体系酸化而带来的催化剂流失, 从而延长催化剂寿命, 降低催化剂成本.
本文采用浸渍法制备了一种双金属铜、钴氧化物催化剂及相关的对照催化剂体系, 利用碳酸氢盐活化 H2O2 用于降解苯酚模拟废水. 通过各种空白实验发现, 负载于γ-Al2O3 表面的钴、铜氧化物催化剂 CuO-Co3O4@γ-Al2O3 具有最好的催化降解活性, 而 CuO@γ-Al2O3, Co3O4@γ-Al2O3, CuO-Co3O4及 CuO 和 Co3O4 的物理混合物均表现出较差的催化性能. 由此可见, 在 CuO-Co3O4@γ-Al2O3 催化剂中, 铜、钴离子在苯酚降解过程中存在协同效应, 这可能与催化剂中钴、铜金属离子的相互作用相关. X 射线衍射和 X 射线光电子能谱结果表明, 反应前后 CuO-Co3O4@γ-Al2O3 催化剂中金属的氧化状态并未发生改变, 在使用过程中钴离子的浸出率可以忽略, 铜离子的浸岀率也仅有 0.6 ppm. 荧光分析实验和自由基捕获实验表明, 只有添加·O2-·OH 的捕获剂能明显抑制降解反应, 因而推测该反应体系对有机物的降解是一个自由基氧化过程, 起关键作用的可能是·O2-·OH.

关键词: 协同效应, 苯酚降解, 铜/钴氧化物催化剂, 机理研究, 碳酸氢盐活化的过氧化氢

Abstract:

The development of new catalytic techniques for wastewater treatment has long attracted much attention from industrial and academic communities. However, because of catalyst leaching during degradation, catalysts can be short lived, and therefore expensive, and unsuitable for use in wastewater treatment. In this work, we developed a bimetallic CuO-Co3O4@γ-Al2O3 catalyst for phenol degradation with bicarbonate-activated H2O2. The weakly basic environment provided by the bicarbonate buffer greatly suppresses leaching of active Cu and Co metal ions from the catalyst. X-ray diffraction and X-ray photoelectron spectroscopy results showed interactions between Cu and Co ions in the CuO-Co3O4@γ-Al2O3 catalyst, and these improve the catalytic activity in phenol degradation. Mechanistic studies using different radical scavengers showed that superoxide and hydroxyl radicals both played significant roles in phenol degradation, whereas singlet oxygen was less important.

Key words: Synergistic effect, Phenol degradation, Copper/cobalt oxide catalyst, Mechanistic study, Bicarbonate-activated H2O2